An Examination of Ashbed Soils Growing Radiata Pine in Gippsland Victoria

SUMMARY

Ashbed soils on which pines had been planted after the native eucalypt vegetation had been cleared, heaped and burnt were compared with non-ashbed soils from adjacent areas which had been cleared and planted.

Tree growth, soil chemical properties and foliar nutrient levels were examined at sites of varying age and a pot trial was established to complement the field trials.

Tree measurements at age 12 years revealed that radiata pine (Pinus radiata D.Don) on ashbed soils had produced 50 percent more timber than stands on adjacent non ashbed soils.

Height growth differences favoured the ashbed sites to the greatest extent at age 5 to 6 years, but decreased and were not signficant at age 12 years.

The ashbed soils had significantly higher percentages of total nitrogen, phosphorus, potassium, manganese and soluble salts in the top 10 inches of soil; the pH of the ashbed soil was also higher by one unit.

Trees on ash bed soils had correspondingly higher percentage of phosphorus and potassium in their foliage compared with trees on adjacent non-ashbed soils but these differences declined with age.

Seedlings grown in pots of ashbed soil also had higher percentages of phosphorus and potassium in their foliage than seedlings in pots of non ashbed soil.